[clang][bytecode] Fix an inconsistency with loop condition jumps (#135530)

When emitting the jump for e.g. a for loop condition, we used to jump
out of the CondScope, leaving the scope initialized, because we skipped
the corresponding Destroy opcode. If that loop was in a loop itself,
that outer loop could then iterate once more, leading to us initializing
a scope that was still initialized.
Fix this by also destroying the scope after the EndLabel.

1 files changed, 2 insertions, 1 deletions

diff --git a/clang/lib/AST/ByteCode/Compiler.h b/clang/lib/AST/ByteCode/Compiler.h
index 256e91772888..858957367d85 100644
--- a/clang/lib/AST/ByteCode/Compiler.h
+++ b/clang/lib/AST/ByteCode/Compiler.h
@@ -531,9 +531,10 @@ public:
     if (!Idx)
       return true;
 
+    // NB: We are *not* resetting Idx here as to allow multiple
+    // calls to destroyLocals().
     bool Success = this->emitDestructors(E);
     this->Ctx->emitDestroy(*Idx, E);
-    this->Idx = std::nullopt;
     return Success;
   }